Method of assembling shell structures consisting of trusses having twisted surface



July 20, 1-965 1' A0 lTOH 3,195,276

METHOD OF ASS LI SHELL STRUCTURES CONSISTING OF TR ES HAVING TWISTEDSURFACE Filed April 23, 1962 5 Sheets-Sheet 1 Mmm Jizly 20, 1965 TAKAOlTOH 9 METHOD OF ASSEMBLING SHELL STRUCTURES CONSISI'ING 0F TRUSSESHAVING TWISTED SURFACE Filed April 23, 1962 3 Sheets-$heet 2:

y 0, 1965 AKAO lTOH 7 METHOD OF ASSEM NG SHELL STRUCTURES CONSISTING OFTRUSSES HAVING TWISTED SURFACE Filed April 25, 1962 3 Sheets-Sheet 3 FI91E n 3 6 o 0 8 & 7g

a T 4' 8 a q METHOD (3F ASSEMBLING SHELL STRUCTURES The presentinvention relates to an improvement in a method of assembling shellstructures consisting of trusses having twisted surface.

The trusses which have heretofore been used as members constituting abuilding structure have been assembled along a plane and such planetrusses have very large resistance to the load acting along the sameplane, but they have disadvantage that they are very easily deformableby the load acting from a direction not on the same plane.

Such a truss forming twisted surfaces consisting of the upper cordmembers and lower cord members which are not in the same plane and theshearing members connecting all cord members together will constitute aso-called hyperbolic paraboloid shell structure, of which deformationsin all directions are sustained at four corners so that such a truss cannot easily deform in all directions according to its own characteristicsand has the shell structure by itself and accordingly a buildingstructure consisting of an assembly of a plurality of such trusses inwave form provides a very strong shell structure cooperating with theabove described truss etfect.

The invention is based on the above consideration and is characterizedin that the lengths of the upper and lower cords which are not locatedin the same plane are divided in proportion respectively and thecorresponding points of division of the upper cord and lower cord andalso the adjacent corresponding points of division connectedsuccessively with diagonals in a form of truss to constitute a unitshell structure having a twisted surface and a number of such unit shellstructure surfaces are arranged in a wave form and connected together asa unit in such manner that the joints of each upper and lower cords anddiagonal members betwen adjacent unit shell structures surfaces meet atthe same corresponding points.

For a better understanding of the invention reference is taken to theaccompanying drawings, in which FIG. 1 is a perspective viewillustrating the manner of connecting several sets of unit trusses,

FIG. 2 is a plan view of the shell structure as shown in FIG. 1,

FIG. 3 is its elevation,

FIG. 4-A and -B show partial side views of its middle portion and theend portion,

FIG. 5 is an explanatory diagram of a method of proportionally dividingthe upper and lower cord members,

FIGS. 6 to 11 are perspective views illustrating several embodiments ofthe shell structures of the invention and,

FIG. 12 is a perspective view for illustrating a form of shell structureshown in FIG. 1 with various addition members attached thereto.

Referring to the drawings, 1 represents an upper cord, 2 a lower cord, 3and 4 diagonals.

According to the invention, the lengths AOB and A'O'B' of the upper cord1 and lower cord 2 which are not located in the same plane areproportionally divided respectively at points l,m,n,O,n,m,l and l',m',n',O,n,m',l and the corresponding points of division, such as 1-1, m-m',n-n', 0-0 and each end of cord United States Patent 0 members 1 and 2such as, A-A and BB' are connected together by means of diagonal members3 and moreover, the corresponding adjacent points, A'l, l'-m, n'-n,n'-O,

B'l are connected together by means of diagonals 4 to form unit shellstructure surfaces T lying on twisted planes, and a number of such unitshell surfaces T are arranged in a wave form and adjacent unit shellstructure surfaces T are connected together as a unit in such mannerthat the joints A,l,m,n,O,B and A,l',m',n,O',B' of each upper cord 1 andadjacent lower cords 2 and diagonals 3 and 4 of adjacent unit shellstructure surfaces T meet at the same corresponding points.

FIG. 5 illustrates an example of a method of proportionally dividingrelatively the lengths of the upper cord and lower cords respectively,wherein the upper cord 1 and lower cord 2 are projected on the sameplane and the point of intersection U of the lines connecting each endof the projected cords PQ and RS respectively is found, and points ofintersection e',f',g' and h of the line connecting the point ofintersection U and any of the points of division e, f, g, h of the cordPQ and the cord RS are found, then these points of intersection will bethe points of projection of proportionally divided points of therequired cord.

FIGS. 6 to 11 illustrate various kinds of shell structures to beobtained by the invention, wherein FIG. 6 represents a dome type, FIG. 7angle shaped type, FIG. 8 single flow type, FIG. 9 an inverted umbrellatype, FIG. 10 an angular umbrella type, and FIG. 11 inverted angularumbrella type.

Since edge surface of each unit shell structure surface of the shellstructure embodying the invention will become a continuation of a waveform, the truss beam obtained by connecting the upper and lower ends ofthe shell structure by tie members 5, 6 and 7 etc. as shown in FIG. 12can carry the end portion of the shell and support the forces actingthereon. If the spacing of each upper cord member 1 is too large to thestrength of a purlin selected at random the diagonal 8 and tie member 9are connected at middle :of the diagonals 3 as shown in FIG. 12 in atriangular form and an auxiliary cord member 10 is supplemented to itsapex, thereby enabling to construct the purlin economically. In FIG. 11,12 represents a supporting column.

When the truss is loaded the lower cord member usually receives tensileload, whilst the upper cord is subject to a compressive load and thediagonal member should resist against a shearing force. Accordingly, aconventional truss constructed in one plane may have very large strengthfor a load acting on the unit plane constituting the truss, but theresistance to the load having a certain angle with the unit plane isvery small. On the contrary, the shell truss according to the invention,as it is so designed that the upper cord and lower cord are not in thesame plane the curved surfaces formed by the upper and lower cords, andthe diagonal connecting these cords constitute a so-called hyperbolicparaboloid shell, of the which the deformation is resisted at fourcorners. Such a shell structure has characteristics that the curvedsurface can not deform in all directions, the surface itself having thenature of a shell structure, the wave shaped structure consisting of acombination of a number of such shell structures has very high strengthand rigidity.

As above described, the invention has the following advantages:

(1) The invention has merit in that the operating quantity at highplaces is reduced and the process can be accelerated since a unit shellstructure surface T is built on the ground and such units are assembledin parallel at high places to constitute a complete structure.

(2) The upper and lower cord members Which are not in the same planerelative tothe other are arranged sive wave form and the truss beamconstructed by joining these upper and lower ends respectively cansupport the reaction at the end of the shell.

(3) When said distance of the adjacent upper cords is too large comparedwith the strength of the purlin with arbitrary selected, an auxiliarycode 10 supported by diagonals 8 arranged at middle of diagonals 3 andthe tie members 9 connecting them can be supplemented, thereby enablingto decide the purlins economically.

(4) By suitably selecting the vertical projected distance of the ends ofthe upper and lower cords, the relation to the top of the pillar will beof somewhat similar construction to that of rigid joint.

(5) 'As a very rigid shell structure connected with each other isresulted there is no necessity of additional tie truss between trussesas in conventional trusses. I

(6) By the above described reason it is advantageous that the section ofmember and numbers can' be economized.

(7) As the unit shell structure surface T is difi'icult to deform itneeds no special auxiliary materials which are inevitable in aconventional truss in the hoisting process in case assembling.

What I claim is: R

l. A truss comprising a lower linear chord member and an upper linearchord member not sharing a plane common to said lower chord member, saidupper chord member being disposed in adjacency to said lower chordmember such that an imaginary longitudinal center line determined bysaid upper linear chord member passes through a horizontal plane throughsaid lower chord member at a point remote from said lower chord member,and said upper chord member being spaced from said lower chord member bylinear connecting members connecting said lower chord member to saidupper chord member such that a first portion of said upper chord memberis spaced further from the adjacent portion of said lower chord memberthen a second portion of said upper chord member is spaced from theadjacent portion of said lower chord member, said connecting memberscomprising a first series of connectingmembers each joining one of aplurality of proportionally spaced points of said lower chord memberwith one of a plurality of corresponding proportionally spaced pointsotsaid upper chord member and a second series of connecting membersjoining one of said proportionally spaced points of said lower chordmember with a next adjacent proportionally spaced point of said upperchord member.

2. A support'structure comprising a plurality of truss members. asclaimed in claim 1 wherein lower chord members of truss members aresecured together and'upper chord members of truss members are securedtogether to form a shell structure comprising a plurality of trusseshaving a plurality of lower chord members in a plane not common to aplurality of upper chord members thereby forming a plurality of twistedplanes between a lower chord member and an upper chord member.

5. A support structure-as claimed in claim 2 further comprising at leastone purlin disposed in a vertical plane common to said lower chordmember and having supporting members joining said purlin with saidconnecting members of adjacent trusses;

References Qited by the Examiner UNITED STATES PATENTS 2,881,713 4/59Stromeyer 5()l2 FOREIGN PATENTS 211,025 9/60 Austria.

CHARLES E. OCONNELL, Primary Examiner.

JACOB SHAPIRO, EARL .T. WITMER, Examiners.

1. A TRUSS COMPRISING A LOWER LINEAR CHORD MEMBER AND AN UPPER LINEARCHORD MEMBER NOT SHARING A PLANE COMMON TO SAID LOWER CHORD MEMBER, SAIDUPPER CHORD MEMBER BEING DISPOSED IN ADJACENCY TO SAID LOWER CHORDMEMBER SUCH THAT AN IMAGINARY LONGITUDINAL CENTER LINE DETERMINED BYSAID UPPER LINEAR CHORD MEMBER PASSES THROUGH A HORIZONTAL PLANE THROUGHSAID LOWER CHORD MEMBER AT A POINT REMOTE FROM SAID LOWER CHORD MEMBER,AND SAID UPPER CHORD MEMBER BEING SPACED FROM SAID LOWER CHORD MEMBER BYLINEAR CONNECTING MEMBERS CONNECTING SAID LOWER CHORD MEMBER TO SAIDUPPER CHORD MEMBER SUCH THAT A FIRST PORTION OF SAID UPPER CHORD MEMBERIS SPACED FURTHER FROM THE ADJACENT PORTION OF SAID LOWER CHORD MEMBERTHEN A SECOND PORTION OF SAID UPPER CHORD MEMBER IS SPACED FROM THEADJACENT PORTION OF SAID LOWER CHORD MEMBER, SAID CONNECTING MEMBERSCOMPRISING A FIRST SERIES OF CONNECTING MEMBERS EACH JOINING ONE OF APLURALITY OF PROPORTIONALLY SPACED POINTS OF SAID LOWER CHORD MEMBERWITH ONE OF A PLURALITY OF CORRESPONDING PROPORTIONALLY SPACED POINTS OFSAID UPPER CHORD MEMBER AND A SECOND SERIES OF CONNECTING MEMBERSJOINING ONE OF SAID PROPORTIONALLY SPACED POINTS OF SAID LOWER CHORDMEMBER WITH A NEXT ADJACENT PROPORTIONALLY SPACED POINT OF SAID UPPERCHORD MEMBER.